Column, capillary optimum, open tubular

Several Interface designs are available for GC/MS and selection depends on the circumstances of the experiment [3-6,8,25,26]. Column flow rates of 1-2 ml/min (adjusted to STP) into the ion source are compatible with modem mass spectrometer vacuxim systems. This is also the optimum floi te range for open tubular capillary columns of conventional lensions. Coupling such columns to a modern mass spectromet er, therefore, presents... 

GC capillary coliunns have a uniform geometry and in the absence of a stationary phase H in is directly proportional to the column internal diameter dc and retention characteristics, k, of the stationary phase film including polar character and film thickness [9-11]. Column design may be evaluated for efficiency and optimum mobile phase velocity using the following equation for proposed by Golay when he developed the theory for open tubular (WCOT) columns [9] ... 

An exception U the possible devdopment of coated open-tubular (capillary) columns, which should prove useftil when very large lvalues are lequiied (708). However, these columns appear more promiang for smaH-molecule separatioas than for largo molecules, because the optimum column diameten for macromolecules are extremely small ([Pg.148]

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